Basic Overall Equipment Qestions

Thalassamania · May 23rd, 2006, 12:08 AM

Clearly I've tried to begin in an overly ambitious fashion. I will start anew with one question per string at a time, more along the model of the other strings I've now had a chance to examine. Please excuse my mistake.

TobinGeorge · May 23rd, 2006, 03:07 AM

Quote: (Originally Posted by Thalassamania)

I think that a good way for me to start is to read the articles beginning with

DIR Explorers>DIR Diving Library?>New to DIR Articles >Are you Doing it Right?

If I may be so bold, I’d like to ask questions about specific sections. You may assume that I’ve read (and I hope understood) material that I’ve not asked about.

Why a “continuous length of webbing.” I can see the advantage to reducing the potential failure points, but that must be weighed against the need to quickly and easily remove the rig. My experiences with “airplane” buckles or fastclips indicate to me that (even in the highest quality incarnation) they are inadequate to the task. However, my experience with doubled stainless steel twist-locks (similar to what was once used on a wetsuit jacket beavertail) suggests that perhaps they might be a reasonable solution.

They really aren't necessary, practice is.

Quote: (Originally Posted by Thalassamania)

No weight belt is worn. Does this not present a potential problem if the rig must be removed while underwater?

I've worn a weight belt if I needed it. Under my harness. I can ditch it just by opening the waist belt and crotch strap first. OTOH ditching is a definite last resort.

Quote: (Originally Posted by Thalassamania)

Given that I can swing just shy of 7 kilos on my lungs, 55 pounds of lift seems excessive (at least for me). Would it be inappropriate to use less?

Yes, often much less.

Quote: (Originally Posted by Thalassamania)

All cylinder valves are kept fully open at all times. Not ½ a turn back? Why?

The 1/4 or 1/2 back is based on obsolete valves prone to sticking.

Quote: (Originally Posted by Thalassamania)

The backup regulator is instantly accessible as it hangs around the neck on an elastic necklace. I have a “cultural” issue with this but I see the logic of it.

????

Quote: (Originally Posted by Thalassamania)

Donating the regulator in your mouth to an out-of-gas diver is one of the cornerstones of the DIR configuration. - This has been a cornerstone of my diving practices and training procedures since the early 1980s. The long hose makes it so much easier and more effective.

All second stage regulators are left finger tight on their hoses so that they can be quickly and easily swapped in the event of failure. The locking pins are removed so that the faceplate can be removed underwater to clear debris. – In fifty years underwater I’ve never needed to do this, but OK, its always the “never saw that one before” that kills the most experienced divers.

I believe this has changed. Carry the required spanner.

Quote: (Originally Posted by Thalassamania)

I leave the light thing for a later date. I do little or no overhead environment diving and so all this concern, while understandable, seems a bit of overkill to me at this juncture.

We see eye to eye on consoles and such, but why clip it off? Every “hard loop” that is created is another potential entanglement point.

That's why no metal to metal connections.

Quote: (Originally Posted by Thalassamania)

And what is this thing with stainless steel bolt-snaps? I’ve seem them fail in a thousand different ways. We typically use spinnaker shackles for the kinds of applications that DIR calls for bolt-snaps.

I've never had a good quality SS bolt snap with SS spring fail. What failures have you seen?

Quote: (Originally Posted by Thalassamania)

I carry my instruments on my left hand, but that’s so I can reach into holes with my right. That’s likely a change I can live with, but with gauges on my right and a light on my left the local lobster population is going to thank you.

Compass on the left, BT on the right, each up almost to the elbow, hasn't proven to be a huge boon to the lobster population.

Quote: (Originally Posted by Thalassamania)

Stiff rubber jet-fins have their straps discarded and replaced with stainless steel spring straps with no quick-release catches to break or otherwise get snagged. – I use the old Fara-Fin, the original stainless steel spring strap from the mid 1970s.

I carry a custom made knife (more tool, than knife if the truth be known) on the inside of my left calf (opposite my handedness). I also carry a set of paramedic sheers, a small line cutter and a small “BC Knife.” All have rings that can be clipped to the spinnaker shackles I wear on each wrist to prevent tool loss.

I use a “butt pack” for additional equipment rather than a “large cargo pocket on the left thigh,” which, at the moment, I lack. I use an opposite securing system, items have rings on them that clip to shackles in the pack; this meshes with my wrist shackles.

I'm pretty committed to avoiding wrist shackles.

Tobin

*peter_steinhoff* · May 23rd, 2006, 03:16 AM

A continous one piece webbing is used because some of the tanks setups are quite heavy (on land), in the range of 60-80kg / 135-175 lbs. Having them break would be disastrous. The harness should be set up so that it is easy to remove the rig by the diver but for emergencies we just cut off the webbing, it's expendable. This setup have been used extensively by cave divers since the late 70s.

No weight belt is worn. That is not 100% true. Usually it is avoided for decompression diving because a dropped weight belt means going to the surface with mandatory decompression. A weight belt or more correctly weight that can be dropped is however needed in some scenarios.

The amount of lift needed is in proportion to the tanks you dive and the amount of gas you need to carry. I use 55 lbs of lift when diving a set of 104s (double 17 liters) and then I have enough lift to carry about 4 Alu 80cuft (11 liters) bottles with nitrox. For single tank diving I use a 27lbs wing. Optimally you should select the smallest wing possible.

All cylinder valves are kept fully open at all times. The reason is to minimize the possibility that you by mistake turn your valves the wrong way when you need to shut them down during a gas leak. For instance closing something when you try to open it and the other way around. When you dive overhead environments like caves it's SOP to check your valves when you get close to the ceiling as it is not uncommon to roll the valves shut.

The logic behind the backup regulator is to have one regulator available at all times. Especially important since we donate what we are breathing to the diver out of gas to guarantee that we hand of a working regulator with a safe gas. That means we have two divers "out of gas" for a short period of time.

All second stage regulators are left finger tight on their hoses so that they can be quickly and easily swapped in the event of failure. That practice has been depreciated since poeple actually forgot to check their second stages and had them come undone during the dive. It was a practice only for very serious diving involving multiple of bottles and breathing gases.

The locking pins are removed so that the faceplate can be removed underwater to clear debris. Diving in environments that have a pins, sticks, clay etc especially when you are leaving bottles on the bottom, like in cave diving, you need to setup your regs like this. It only applies to some regulator brands however.

Clipping off everything is to keep it to keep the equipment streamlined and not hang down below you when diving in a prone position. All hoses are generally cut to length and routed so they don't stick out.

Bolt snaps are used because they can be manipulated one handed and they won't clip into lines or other things by mistake. I don't know what a spinnaker shackle is so can't comment on that. Stainless steel is chosen over brass because they hold up better in salt water and are smoother so they won't cut your thumb. The skin becomes really soft when doing multiple hour dives without gloves.

Usually we carry a bottom timer on the right wrist and a compass on the left. It's because we can use our light to illuminate the bottom timer and the light is kept in our left hand so we can donate gas without blinding our buddy. Another reason is since we ride the scooters with our right hand we need to have the light in our left to look around. Everything is here very much optimized for diving in dark environments. Generally we also favor low profile instrument so they won't catch on things.

A knife is carried on our waist belt so it can be reached from either hand. Every boltsnap is tied on by cave line (nylon or similar material) and can easily be cut off with a knife if an entaglement should warrrant it. Knife located on the legs are not used since they are a severe entanglement hazard when diving amongst guidelines. We also dive in a prone position with bent knees to be streamlined and able to swim very close to bottom sediment without stirring it up. For ocean diving a pair of sheers is usually carried clipped off in the pocket. Some people also carry a backup line cutter on their light handles.

We carrry additional items in our suit pockets which are located on the outside part of the thighst. That makes them easliy accessible and reasonably streamlined. Usually items are clipped off in the pocket to a bungee cord. Most people have a D-ring located where I assume your butt pack is located. That is sometimes also used to clip of equipment. Personally I seldom use it because it can be a challenge sometimes to reach around when you carry a lot of additional bottles. Also having items (some of them security related) in a pocket means they are protected and you won't place your heavy double tanks on them while suiting up.

Hope that explains some of your questions.
I tried to keep it short-ish so that I would not get too tired from typing

I'm glad to be more specific if need be.

Cheers,
Peter

Thalassamania · May 23rd, 2006, 03:42 AM

Peter,

Thank you very much. Again I applogize for starting off with a magnum opus that demanded so much of your poor tired fingers. I will be posting my second order questions and thoughts shortly, please do not feel that you need answer them all at once. While you and I continue this string I'm using other strings that break down the questions into bite size chunks that are easier to deal with.

Thanks again

maccajim · May 23rd, 2006, 03:45 AM

If you go to www.gue.com you will find all the answers to equipment considerations it is pretty comprehensive and a good starting point.

Thalassamania · May 23rd, 2006, 04:24 AM

Quote: (Originally Posted by maccajim)

If you go to www.gue.com you will find all the answers to equipment considerations it is pretty comprehensive and a good starting point.

I've been there and read it all quite avidly, but frankly and trying not to take too much on myself, I did not find it really useful.

I fear that my questions and concerns are not of the general nature that the web site is designed to answer. Thought I did find enough common ground to encourage me to work my way here.

Thalassamania · May 23rd, 2006, 05:30 AM

Quote: (Originally Posted by TobinGeorge)

They really aren't necessary, practice is.

Yes, its not that difficult to “chicken wing” out of a continuous harness.

Quote: (Originally Posted by TobinGeorge)

I've worn a weight belt if I needed it. Under my harness. I can ditch it just by opening the waist belt and crotch strap first. OTOH ditching is a definite last resort.

Weight belt under the harness is fine; weight harness under the harness is fine. My concern is not removal but rather control if I had to doff and don my rig.

Quote: (Originally Posted by TobinGeorge)

The 1/4 or 1/2 back is based on obsolete valves prone to sticking.

Unfortunately I still have some such valves, perhaps they need to retire.

Quote: (Originally Posted by TobinGeorge)

????

Within the SDC there are a few concepts that mitigate against comfort with a neck strap (which is not to say that I’m not going to try it). The first is the idea that anytime you create a loop you create an entanglement hazard. The second is that there was an accident (real or imagined, you know how it is) many years ago in which a diver supposedly tried to snatch a regulator away from a neck-strap equipped diver. The snatcher lost his grip, the regulator snapped back and broke the “donor’s” jaw and he drowned. The third is the idea that when you loose something you cannot rely on a secondary attachment point. You go back to the primary attachment point and recover it from there (in the case of the auxiliary regulator the ability to perform a “look ma, no hands” recovery is, I thing, enough to overcome the upfront objections, but then there’s a lifetime of acculturation and drill.

Quote: (Originally Posted by TobinGeorge)

I believe this has changed. Carry the required spanner.

Hmmm … Underwater Equipment Repair Specialist … can I get a patch? <G>

Quote: (Originally Posted by TobinGeorge)

That's why no metal to metal connections.

Excellent point.

Quote: (Originally Posted by TobinGeorge)

I've never had a good quality SS bolt snap with SS spring fail. What failures have you seen?

See my other post concerning the Blue Water Diving fatality.

Quote: (Originally Posted by TobinGeorge)

Compass on the left … almost to the elbow

I think in that configuration I’d have trouble keeping the lubber line parallel to my direction of travel.

Quote: (Originally Posted by TobinGeorge)

I'm pretty committed to avoiding wrist shackles

Please, no offense intended, sometimes I’m a little dense. Are you joking about handcuffs or do you avoid wrist lanyards in general. That system has saved an awful lot of missions for me.

Thalassamania · May 23rd, 2006, 06:05 AM

Quote: (Originally Posted by peter_steinhoff)

A continous one piece webbing is used because some of the tanks setups are quite heavy (on land), in the range of 60-80kg / 135-175 lbs. Having them break would be disastrous. The harness should be set up so that it is easy to remove the rig by the diver but for emergencies we just cut off the webbing, it's expendable. This setup have been used extensively by cave divers since the late 70s.

Clear

Quote: (Originally Posted by peter_steinhoff)

No weight belt is worn. That is not 100% true. Usually it is avoided for decompression diving because a dropped weight belt means going to the surface with mandatory decompression. A weight belt or more correctly weight that can be dropped is however needed in some scenarios.

Is a doff and don of the rig not quite difficult at depth with all the weight on the rig?

Quote: (Originally Posted by peter_steinhoff)

The amount of lift needed is in proportion to the tanks you dive and the amount of gas you need to carry. I use 55 lbs of lift when diving a set of 104s (double 17 liters) and then I have enough lift to carry about 4 Alu 80cuft (11 liters) bottles with nitrox. For single tank diving I use a 27lbs wing. Optimally you should select the smallest wing possible.

Clear

Quote: (Originally Posted by peter_steinhoff)

All cylinder valves are kept fully open at all times. The reason is to minimize the possibility that you by mistake turn your valves the wrong way when you need to shut them down during a gas leak. For instance closing something when you try to open it and the other way around. When you dive overhead environments like caves it's SOP to check your valves when you get close to the ceiling as it is not uncommon to roll the valves shut.

Proper planning and drill should easily avoid the possibility that one might mistakenly the valves the wrong way.

Quote: (Originally Posted by peter_steinhoff)

The logic behind the backup regulator is to have one regulator available at all times. Especially important since we donate what we are breathing to the diver out of gas to guarantee that we hand of a working regulator with a safe gas. That means we have two divers "out of gas" for a short period of time.

Our procedures are the same.

Quote: (Originally Posted by peter_steinhoff)

All second stage regulators are left finger tight on their hoses so that they can be quickly and easily swapped in the event of failure. That practice has been depreciated since poeple actually forgot to check their second stages and had them come undone during the dive. It was a practice only for very serious diving involving multiple of bottles and breathing gases.

OK, I woun’t worry about it at this point.

Quote: (Originally Posted by peter_steinhoff)

The locking pins are removed so that the faceplate can be removed underwater to clear debris. Diving in environments that have a pins, sticks, clay etc especially when you are leaving bottles on the bottom, like in cave diving, you need to setup your regs like this. It only applies to some regulator brands however.

Not being a cave diver I obviously do not fully grasp the issue.

Quote: (Originally Posted by peter_steinhoff)

Clipping off everything is to keep it to keep the equipment streamlined and not hang down below you when diving in a prone position. All hoses are generally cut to length and routed so they don't stick out.

I agree with the final desired result (how could one not), but I think that I can accomplish the same goal without the clips.

Quote: (Originally Posted by peter_steinhoff)

Bolt snaps are used because they can be manipulated one handed and they won't clip into lines or other things by mistake. I don't know what a spinnaker shackle is so can't comment on that. Stainless steel is chosen over brass because they hold up better in salt water and are smoother so they won't cut your thumb. The skin becomes really soft when doing multiple hour dives without gloves.

Got to stay out of that warm fresh water, its real hard on your skin.

Quote: (Originally Posted by peter_steinhoff)

Usually we carry a bottom timer on the right wrist and a compass on the left. It's because we can use our light to illuminate the bottom timer and the light is kept in our left hand so we can donate gas without blinding our buddy. Another reason is since we ride the scooters with our right hand we need to have the light in our left to look around. Everything is here very much optimized for diving in dark environments. Generally we also favor low profile instrument so they won't catch on things.

OK

Quote: (Originally Posted by peter_steinhoff)

A knife is carried on our waist belt so it can be reached from either hand. Every boltsnap is tied on by cave line (nylon or similar material) and can easily be cut off with a knife if an entaglement should warrrant it. Knife located on the legs are not used since they are a severe entanglement hazard when diving amongst guidelines. We also dive in a prone position with bent knees to be streamlined and able to swim very close to bottom sediment without stirring it up. For ocean diving a pair of sheers is usually carried clipped off in the pocket. Some people also carry a backup line cutter on their light handles.

I spend several decades in the Kelp of Northern California and a knife on my inside calf never seriously fouled, perhaps guidelines are different.

Quote: (Originally Posted by peter_steinhoff)

We carrry additional items in our suit pockets which are located on the outside part of the thighst. That makes them easliy accessible and reasonably streamlined. Usually items are clipped off in the pocket to a bungee cord. Most people have a D-ring located where I assume your butt pack is located. That is sometimes also used to clip of equipment. Personally I seldom use it because it can be a challenge sometimes to reach around when you carry a lot of additional bottles. Also having items (some of them security related) in a pocket means they are protected and you won't place your heavy double tanks on them while suiting up.

I’m fairly flexible, but the protection angle is a reasonable one.

maccajim · May 23rd, 2006, 09:10 AM

Hiya Thalassamania ,
you seem to have a lot of time why not do some more reading all the answers for your questions are out there either here or join www.thedecostop.com they have a pretty large forum with dir posts.
Then book in for Dirf or dive with some local dir diversyou cant learn much on the internet.

*peter_steinhoff* · May 25th, 2006, 01:35 AM

Quote: (Originally Posted by Thalassamania)

Is a doff and don of the rig not quite difficult at depth with all the weight on the rig?

Yes, it is quite difficult especially in a drysuit with thick underwear. We have however not found an emergency scenario where the need or the benefit of removing our tanks at depth would outweight the risk. So as a general rule we never remove our tanks at depth.

There are some extreme entanglement that could potentially call for it but we try to avoid that by being aware of our surroundings, having a very streamlined and slick equipment configuration (where we also can remove all auxilliary items) and also always dive with a buddy that can assist (solo-diving is considered unsafe).

Quote: (Originally Posted by Thalassamania)

Proper planning and drill should easily avoid the possibility that one might mistakenly the valves the wrong way.

I agree and I don't believe it makes a big difference as long as the valve is almost open but what to be avoided is the practice of leaving some valves just partially open so they can be closed fast in an emergency. That has been a source of some real confusion during the dive.

Quote: (Originally Posted by Thalassamania)

Not being a cave diver I obviously do not fully grasp the issue.

Cave diving can be everything from swimming or scootering in big 100ft wide passages with 300ft of visibility to wiggling through a clay tunnel barely wider than your shoulders in zero viz. The pictures and videos available on the net naturally doesn't show the second scenario. But I'm sure you can imagine it

Quote: (Originally Posted by Thalassamania)

I agree with the final desired result (how could one not), but I think that I can accomplish the same goal without the clips.

Maybe, but remember that we dive in a prone position and don't want anything hanging below us to catch on lines. You could of course tuck your spg somewhere but then again it needs to be accessible even when you carry lot's of equipment.

Quote: (Originally Posted by Thalassamania)

I spend several decades in the Kelp of Northern California and a knife on my inside calf never seriously fouled, perhaps guidelines are different.

I assume so. Cave divers abandoned carrying cutting devices on their legs probably more than thirty years ago.

Even though the DIR configuration and procedures originated from extreme cave diving most of the divers that developed the system where avid ocean divers from the start so it has been a natural process to keep the base standardized system identical to both environments.

I don't have many pictures of myself going diving but I will supply some so you can get a better idea of what the configuration could look like.

Cheers,
Peter

May 23rd, 2006, 12:08 AM	#1 (permalink)
Thalassamania(Offline) New Member Join Date: May 2006 Location: Most Oceans and Seas Posts: 66	Basic Overall Equipment Qestions Clearly I've tried to begin in an overly ambitious fashion. I will start anew with one question per string at a time, more along the model of the other strings I've now had a chance to examine. Please excuse my mistake. __________________ “I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it.” Thomas Jefferson Last edited by Thalassamania; May 23rd, 2006 at 02:37 AM. Reason: My own stupidity

May 23rd, 2006, 03:16 AM	#3 (permalink)
peter_steinhoff(Offline) Instructor candidate Join Date: Dec 2005 Location: Sweden & Florida Posts: 205	A continous one piece webbing is used because some of the tanks setups are quite heavy (on land), in the range of 60-80kg / 135-175 lbs. Having them break would be disastrous. The harness should be set up so that it is easy to remove the rig by the diver but for emergencies we just cut off the webbing, it's expendable. This setup have been used extensively by cave divers since the late 70s. No weight belt is worn. That is not 100% true. Usually it is avoided for decompression diving because a dropped weight belt means going to the surface with mandatory decompression. A weight belt or more correctly weight that can be dropped is however needed in some scenarios. The amount of lift needed is in proportion to the tanks you dive and the amount of gas you need to carry. I use 55 lbs of lift when diving a set of 104s (double 17 liters) and then I have enough lift to carry about 4 Alu 80cuft (11 liters) bottles with nitrox. For single tank diving I use a 27lbs wing. Optimally you should select the smallest wing possible. All cylinder valves are kept fully open at all times. The reason is to minimize the possibility that you by mistake turn your valves the wrong way when you need to shut them down during a gas leak. For instance closing something when you try to open it and the other way around. When you dive overhead environments like caves it's SOP to check your valves when you get close to the ceiling as it is not uncommon to roll the valves shut. The logic behind the backup regulator is to have one regulator available at all times. Especially important since we donate what we are breathing to the diver out of gas to guarantee that we hand of a working regulator with a safe gas. That means we have two divers "out of gas" for a short period of time. All second stage regulators are left finger tight on their hoses so that they can be quickly and easily swapped in the event of failure. That practice has been depreciated since poeple actually forgot to check their second stages and had them come undone during the dive. It was a practice only for very serious diving involving multiple of bottles and breathing gases. The locking pins are removed so that the faceplate can be removed underwater to clear debris. Diving in environments that have a pins, sticks, clay etc especially when you are leaving bottles on the bottom, like in cave diving, you need to setup your regs like this. It only applies to some regulator brands however. Clipping off everything is to keep it to keep the equipment streamlined and not hang down below you when diving in a prone position. All hoses are generally cut to length and routed so they don't stick out. Bolt snaps are used because they can be manipulated one handed and they won't clip into lines or other things by mistake. I don't know what a spinnaker shackle is so can't comment on that. Stainless steel is chosen over brass because they hold up better in salt water and are smoother so they won't cut your thumb. The skin becomes really soft when doing multiple hour dives without gloves. Usually we carry a bottom timer on the right wrist and a compass on the left. It's because we can use our light to illuminate the bottom timer and the light is kept in our left hand so we can donate gas without blinding our buddy. Another reason is since we ride the scooters with our right hand we need to have the light in our left to look around. Everything is here very much optimized for diving in dark environments. Generally we also favor low profile instrument so they won't catch on things. A knife is carried on our waist belt so it can be reached from either hand. Every boltsnap is tied on by cave line (nylon or similar material) and can easily be cut off with a knife if an entaglement should warrrant it. Knife located on the legs are not used since they are a severe entanglement hazard when diving amongst guidelines. We also dive in a prone position with bent knees to be streamlined and able to swim very close to bottom sediment without stirring it up. For ocean diving a pair of sheers is usually carried clipped off in the pocket. Some people also carry a backup line cutter on their light handles. We carrry additional items in our suit pockets which are located on the outside part of the thighst. That makes them easliy accessible and reasonably streamlined. Usually items are clipped off in the pocket to a bungee cord. Most people have a D-ring located where I assume your butt pack is located. That is sometimes also used to clip of equipment. Personally I seldom use it because it can be a challenge sometimes to reach around when you carry a lot of additional bottles. Also having items (some of them security related) in a pocket means they are protected and you won't place your heavy double tanks on them while suiting up. Hope that explains some of your questions. I tried to keep it short-ish so that I would not get too tired from typing I'm glad to be more specific if need be. Cheers, Peter __________________ Peter Steinhoff GUE DIR-F, Tech1, Tech2, Cave1, Cave2, Cave3, RB80-1&2, DIR-F/Cave Instructor Candidate. NAUI Tec Instructor (Trimix, Technical DPV, Technical Wreck Penenetration etc) WKPP Support Diver, Halcyon Product Development Team, Gavinscooter Representative. Various IANTD, NSS-CDS, NACD, PADI & NAUI. ---------------------------------------------- http://dir-diver.com http://peter.steinhoff.se (swedish only) Last edited by peter_steinhoff; May 23rd, 2006 at 03:26 AM.

May 23rd, 2006, 03:42 AM	#4 (permalink)
Thalassamania(Offline) New Member Join Date: May 2006 Location: Most Oceans and Seas Posts: 66	Peter, Thank you very much. Again I applogize for starting off with a magnum opus that demanded so much of your poor tired fingers. I will be posting my second order questions and thoughts shortly, please do not feel that you need answer them all at once. While you and I continue this string I'm using other strings that break down the questions into bite size chunks that are easier to deal with. Thanks again __________________ “I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it.” Thomas Jefferson

May 23rd, 2006, 03:45 AM	#5 (permalink)
maccajim(Offline) New Member Join Date: Nov 2005 Location: Sydney Posts: 97	goto www.gue.com If you go to www.gue.com you will find all the answers to equipment considerations it is pretty comprehensive and a good starting point.

May 23rd, 2006, 04:24 AM	#6 (permalink)
Thalassamania(Offline) New Member Join Date: May 2006 Location: Most Oceans and Seas Posts: 66	Quote: (Originally Posted by maccajim) If you go to www.gue.com you will find all the answers to equipment considerations it is pretty comprehensive and a good starting point. I've been there and read it all quite avidly, but frankly and trying not to take too much on myself, I did not find it really useful. I fear that my questions and concerns are not of the general nature that the web site is designed to answer. Thought I did find enough common ground to encourage me to work my way here. __________________ “I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it.” Thomas Jefferson

May 23rd, 2006, 03:07 AM	#2 (permalink)
TobinGeorge (Online) New Member Join Date: Nov 2005 Location: Southern California Posts: 566	Quote: (Originally Posted by Thalassamania) I think that a good way for me to start is to read the articles beginning with DIR Explorers>DIR Diving Library?>New to DIR Articles >Are you Doing it Right? If I may be so bold, I’d like to ask questions about specific sections. You may assume that I’ve read (and I hope understood) material that I’ve not asked about. Why a “continuous length of webbing.” I can see the advantage to reducing the potential failure points, but that must be weighed against the need to quickly and easily remove the rig. My experiences with “airplane” buckles or fastclips indicate to me that (even in the highest quality incarnation) they are inadequate to the task. However, my experience with doubled stainless steel twist-locks (similar to what was once used on a wetsuit jacket beavertail) suggests that perhaps they might be a reasonable solution. They really aren't necessary, practice is. Quote: (Originally Posted by Thalassamania) No weight belt is worn. Does this not present a potential problem if the rig must be removed while underwater? I've worn a weight belt if I needed it. Under my harness. I can ditch it just by opening the waist belt and crotch strap first. OTOH ditching is a definite last resort. Quote: (Originally Posted by Thalassamania) Given that I can swing just shy of 7 kilos on my lungs, 55 pounds of lift seems excessive (at least for me). Would it be inappropriate to use less? Yes, often much less. Quote: (Originally Posted by Thalassamania) All cylinder valves are kept fully open at all times. Not ½ a turn back? Why? The 1/4 or 1/2 back is based on obsolete valves prone to sticking. Quote: (Originally Posted by Thalassamania) The backup regulator is instantly accessible as it hangs around the neck on an elastic necklace. I have a “cultural” issue with this but I see the logic of it. ???? Quote: (Originally Posted by Thalassamania) Donating the regulator in your mouth to an out-of-gas diver is one of the cornerstones of the DIR configuration. - This has been a cornerstone of my diving practices and training procedures since the early 1980s. The long hose makes it so much easier and more effective. All second stage regulators are left finger tight on their hoses so that they can be quickly and easily swapped in the event of failure. The locking pins are removed so that the faceplate can be removed underwater to clear debris. – In fifty years underwater I’ve never needed to do this, but OK, its always the “never saw that one before” that kills the most experienced divers. I believe this has changed. Carry the required spanner. Quote: (Originally Posted by Thalassamania) I leave the light thing for a later date. I do little or no overhead environment diving and so all this concern, while understandable, seems a bit of overkill to me at this juncture. We see eye to eye on consoles and such, but why clip it off? Every “hard loop” that is created is another potential entanglement point. That's why no metal to metal connections. Quote: (Originally Posted by Thalassamania) And what is this thing with stainless steel bolt-snaps? I’ve seem them fail in a thousand different ways. We typically use spinnaker shackles for the kinds of applications that DIR calls for bolt-snaps. I've never had a good quality SS bolt snap with SS spring fail. What failures have you seen? Quote: (Originally Posted by Thalassamania) I carry my instruments on my left hand, but that’s so I can reach into holes with my right. That’s likely a change I can live with, but with gauges on my right and a light on my left the local lobster population is going to thank you. Compass on the left, BT on the right, each up almost to the elbow, hasn't proven to be a huge boon to the lobster population. Quote: (Originally Posted by Thalassamania) Stiff rubber jet-fins have their straps discarded and replaced with stainless steel spring straps with no quick-release catches to break or otherwise get snagged. – I use the old Fara-Fin, the original stainless steel spring strap from the mid 1970s. I carry a custom made knife (more tool, than knife if the truth be known) on the inside of my left calf (opposite my handedness). I also carry a set of paramedic sheers, a small line cutter and a small “BC Knife.” All have rings that can be clipped to the spinnaker shackles I wear on each wrist to prevent tool loss. I use a “butt pack” for additional equipment rather than a “large cargo pocket on the left thigh,” which, at the moment, I lack. I use an opposite securing system, items have rings on them that clip to shackles in the pack; this meshes with my wrist shackles. I'm pretty committed to avoiding wrist shackles. Tobin

May 23rd, 2006, 05:30 AM	#7 (permalink)
Thalassamania(Offline) New Member Join Date: May 2006 Location: Most Oceans and Seas Posts: 66	Quote: (Originally Posted by TobinGeorge) They really aren't necessary, practice is. Yes, its not that difficult to “chicken wing” out of a continuous harness. Quote: (Originally Posted by TobinGeorge) I've worn a weight belt if I needed it. Under my harness. I can ditch it just by opening the waist belt and crotch strap first. OTOH ditching is a definite last resort. Weight belt under the harness is fine; weight harness under the harness is fine. My concern is not removal but rather control if I had to doff and don my rig. Quote: (Originally Posted by TobinGeorge) The 1/4 or 1/2 back is based on obsolete valves prone to sticking. Unfortunately I still have some such valves, perhaps they need to retire. Quote: (Originally Posted by TobinGeorge) ???? Within the SDC there are a few concepts that mitigate against comfort with a neck strap (which is not to say that I’m not going to try it). The first is the idea that anytime you create a loop you create an entanglement hazard. The second is that there was an accident (real or imagined, you know how it is) many years ago in which a diver supposedly tried to snatch a regulator away from a neck-strap equipped diver. The snatcher lost his grip, the regulator snapped back and broke the “donor’s” jaw and he drowned. The third is the idea that when you loose something you cannot rely on a secondary attachment point. You go back to the primary attachment point and recover it from there (in the case of the auxiliary regulator the ability to perform a “look ma, no hands” recovery is, I thing, enough to overcome the upfront objections, but then there’s a lifetime of acculturation and drill. Quote: (Originally Posted by TobinGeorge) I believe this has changed. Carry the required spanner. Hmmm … Underwater Equipment Repair Specialist … can I get a patch? <G> Quote: (Originally Posted by TobinGeorge) That's why no metal to metal connections. Excellent point. Quote: (Originally Posted by TobinGeorge) I've never had a good quality SS bolt snap with SS spring fail. What failures have you seen? See my other post concerning the Blue Water Diving fatality. Quote: (Originally Posted by TobinGeorge) Compass on the left … almost to the elbow I think in that configuration I’d have trouble keeping the lubber line parallel to my direction of travel. Quote: (Originally Posted by TobinGeorge) I'm pretty committed to avoiding wrist shackles Please, no offense intended, sometimes I’m a little dense. Are you joking about handcuffs or do you avoid wrist lanyards in general. That system has saved an awful lot of missions for me. __________________ “I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it.” Thomas Jefferson

May 23rd, 2006, 06:05 AM	#8 (permalink)
Thalassamania(Offline) New Member Join Date: May 2006 Location: Most Oceans and Seas Posts: 66	Quote: (Originally Posted by peter_steinhoff) A continous one piece webbing is used because some of the tanks setups are quite heavy (on land), in the range of 60-80kg / 135-175 lbs. Having them break would be disastrous. The harness should be set up so that it is easy to remove the rig by the diver but for emergencies we just cut off the webbing, it's expendable. This setup have been used extensively by cave divers since the late 70s. Clear Quote: (Originally Posted by peter_steinhoff) No weight belt is worn. That is not 100% true. Usually it is avoided for decompression diving because a dropped weight belt means going to the surface with mandatory decompression. A weight belt or more correctly weight that can be dropped is however needed in some scenarios. Is a doff and don of the rig not quite difficult at depth with all the weight on the rig? Quote: (Originally Posted by peter_steinhoff) The amount of lift needed is in proportion to the tanks you dive and the amount of gas you need to carry. I use 55 lbs of lift when diving a set of 104s (double 17 liters) and then I have enough lift to carry about 4 Alu 80cuft (11 liters) bottles with nitrox. For single tank diving I use a 27lbs wing. Optimally you should select the smallest wing possible. Clear Quote: (Originally Posted by peter_steinhoff) All cylinder valves are kept fully open at all times. The reason is to minimize the possibility that you by mistake turn your valves the wrong way when you need to shut them down during a gas leak. For instance closing something when you try to open it and the other way around. When you dive overhead environments like caves it's SOP to check your valves when you get close to the ceiling as it is not uncommon to roll the valves shut. Proper planning and drill should easily avoid the possibility that one might mistakenly the valves the wrong way. Quote: (Originally Posted by peter_steinhoff) The logic behind the backup regulator is to have one regulator available at all times. Especially important since we donate what we are breathing to the diver out of gas to guarantee that we hand of a working regulator with a safe gas. That means we have two divers "out of gas" for a short period of time. Our procedures are the same. Quote: (Originally Posted by peter_steinhoff) All second stage regulators are left finger tight on their hoses so that they can be quickly and easily swapped in the event of failure. That practice has been depreciated since poeple actually forgot to check their second stages and had them come undone during the dive. It was a practice only for very serious diving involving multiple of bottles and breathing gases. OK, I woun’t worry about it at this point. Quote: (Originally Posted by peter_steinhoff) The locking pins are removed so that the faceplate can be removed underwater to clear debris. Diving in environments that have a pins, sticks, clay etc especially when you are leaving bottles on the bottom, like in cave diving, you need to setup your regs like this. It only applies to some regulator brands however. Not being a cave diver I obviously do not fully grasp the issue. Quote: (Originally Posted by peter_steinhoff) Clipping off everything is to keep it to keep the equipment streamlined and not hang down below you when diving in a prone position. All hoses are generally cut to length and routed so they don't stick out. I agree with the final desired result (how could one not), but I think that I can accomplish the same goal without the clips. Quote: (Originally Posted by peter_steinhoff) Bolt snaps are used because they can be manipulated one handed and they won't clip into lines or other things by mistake. I don't know what a spinnaker shackle is so can't comment on that. Stainless steel is chosen over brass because they hold up better in salt water and are smoother so they won't cut your thumb. The skin becomes really soft when doing multiple hour dives without gloves. Got to stay out of that warm fresh water, its real hard on your skin. Quote: (Originally Posted by peter_steinhoff) Usually we carry a bottom timer on the right wrist and a compass on the left. It's because we can use our light to illuminate the bottom timer and the light is kept in our left hand so we can donate gas without blinding our buddy. Another reason is since we ride the scooters with our right hand we need to have the light in our left to look around. Everything is here very much optimized for diving in dark environments. Generally we also favor low profile instrument so they won't catch on things. OK Quote: (Originally Posted by peter_steinhoff) A knife is carried on our waist belt so it can be reached from either hand. Every boltsnap is tied on by cave line (nylon or similar material) and can easily be cut off with a knife if an entaglement should warrrant it. Knife located on the legs are not used since they are a severe entanglement hazard when diving amongst guidelines. We also dive in a prone position with bent knees to be streamlined and able to swim very close to bottom sediment without stirring it up. For ocean diving a pair of sheers is usually carried clipped off in the pocket. Some people also carry a backup line cutter on their light handles. I spend several decades in the Kelp of Northern California and a knife on my inside calf never seriously fouled, perhaps guidelines are different. Quote: (Originally Posted by peter_steinhoff) We carrry additional items in our suit pockets which are located on the outside part of the thighst. That makes them easliy accessible and reasonably streamlined. Usually items are clipped off in the pocket to a bungee cord. Most people have a D-ring located where I assume your butt pack is located. That is sometimes also used to clip of equipment. Personally I seldom use it because it can be a challenge sometimes to reach around when you carry a lot of additional bottles. Also having items (some of them security related) in a pocket means they are protected and you won't place your heavy double tanks on them while suiting up. I’m fairly flexible, but the protection angle is a reasonable one. __________________ “I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it.” Thomas Jefferson

May 23rd, 2006, 09:10 AM	#9 (permalink)
maccajim(Offline) New Member Join Date: Nov 2005 Location: Sydney Posts: 97	all your quesitons are basic Hiya Thalassamania , you seem to have a lot of time why not do some more reading all the answers for your questions are out there either here or join www.thedecostop.com they have a pretty large forum with dir posts. Then book in for Dirf or dive with some local dir diversyou cant learn much on the internet.

May 25th, 2006, 01:35 AM	#10 (permalink)
peter_steinhoff(Offline) Instructor candidate Join Date: Dec 2005 Location: Sweden & Florida Posts: 205	Quote: (Originally Posted by Thalassamania) Is a doff and don of the rig not quite difficult at depth with all the weight on the rig? Yes, it is quite difficult especially in a drysuit with thick underwear. We have however not found an emergency scenario where the need or the benefit of removing our tanks at depth would outweight the risk. So as a general rule we never remove our tanks at depth. There are some extreme entanglement that could potentially call for it but we try to avoid that by being aware of our surroundings, having a very streamlined and slick equipment configuration (where we also can remove all auxilliary items) and also always dive with a buddy that can assist (solo-diving is considered unsafe). Quote: (Originally Posted by Thalassamania) Proper planning and drill should easily avoid the possibility that one might mistakenly the valves the wrong way. I agree and I don't believe it makes a big difference as long as the valve is almost open but what to be avoided is the practice of leaving some valves just partially open so they can be closed fast in an emergency. That has been a source of some real confusion during the dive. Quote: (Originally Posted by Thalassamania) Not being a cave diver I obviously do not fully grasp the issue. Cave diving can be everything from swimming or scootering in big 100ft wide passages with 300ft of visibility to wiggling through a clay tunnel barely wider than your shoulders in zero viz. The pictures and videos available on the net naturally doesn't show the second scenario. But I'm sure you can imagine it Quote: (Originally Posted by Thalassamania) I agree with the final desired result (how could one not), but I think that I can accomplish the same goal without the clips. Maybe, but remember that we dive in a prone position and don't want anything hanging below us to catch on lines. You could of course tuck your spg somewhere but then again it needs to be accessible even when you carry lot's of equipment. Quote: (Originally Posted by Thalassamania) I spend several decades in the Kelp of Northern California and a knife on my inside calf never seriously fouled, perhaps guidelines are different. I assume so. Cave divers abandoned carrying cutting devices on their legs probably more than thirty years ago. Even though the DIR configuration and procedures originated from extreme cave diving most of the divers that developed the system where avid ocean divers from the start so it has been a natural process to keep the base standardized system identical to both environments. I don't have many pictures of myself going diving but I will supply some so you can get a better idea of what the configuration could look like. Cheers, Peter __________________ Peter Steinhoff GUE DIR-F, Tech1, Tech2, Cave1, Cave2, Cave3, RB80-1&2, DIR-F/Cave Instructor Candidate. NAUI Tec Instructor (Trimix, Technical DPV, Technical Wreck Penenetration etc) WKPP Support Diver, Halcyon Product Development Team, Gavinscooter Representative. Various IANTD, NSS-CDS, NACD, PADI & NAUI. ---------------------------------------------- http://dir-diver.com http://peter.steinhoff.se (swedish only)